In February 2011, Google announced the Panda update, which penalizes websites containing content duplicated from other websites and sources. Historically websites have copied content from one another and benefited in search engine rankings by engaging in this practice. However, Google implemented a new system which punishes sites whose content is not unique.[36] The 2012 Google Penguin attempted to penalize websites that used manipulative techniques to improve their rankings on the search engine.[37] Although Google Penguin has been presented as an algorithm aimed at fighting web spam, it really focuses on spammy links[38] by gauging the quality of the sites the links are coming from. The 2013 Google Hummingbird update featured an algorithm change designed to improve Google's natural language processing and semantic understanding of web pages. Hummingbird's language processing system falls under the newly recognized term of 'Conversational Search' where the system pays more attention to each word in the query in order to better match the pages to the meaning of the query rather than a few words [39]. With regards to the changes made to search engine optimization, for content publishers and writers, Hummingbird is intended to resolve issues by getting rid of irrelevant content and spam, allowing Google to produce high-quality content and rely on them to be 'trusted' authors.
QUOTE: “So it’s not something where we’d say, if your website was previously affected, then it will always be affected. Or if it wasn’t previously affected, it will never be affected.… sometimes we do change the criteria…. category pages…. (I) wouldn’t see that as something where Panda would say, this looks bad.… Ask them the questions from the Panda blog post….. usability, you need to work on.“ John Mueller, Google.
SEO is not an appropriate strategy for every website, and other Internet marketing strategies can be more effective, such as paid advertising through pay per click (PPC) campaigns, depending on the site operator's goals. Search engine marketing (SEM) is the practice of designing, running and optimizing search engine ad campaigns.[56] Its difference from SEO is most simply depicted as the difference between paid and unpaid priority ranking in search results. Its purpose regards prominence more so than relevance; website developers should regard SEM with the utmost importance with consideration to visibility as most navigate to the primary listings of their search.[57] A successful Internet marketing campaign may also depend upon building high quality web pages to engage and persuade, setting up analytics programs to enable site owners to measure results, and improving a site's conversion rate.[58] In November 2015, Google released a full 160 page version of its Search Quality Rating Guidelines to the public,[59] which revealed a shift in their focus towards "usefulness" and mobile search. In recent years the mobile market has exploded, overtaking the use of desktops, as shown in by StatCounter in October 2016 where they analyzed 2.5 million websites and found that 51.3% of the pages were loaded by a mobile device [60]. Google has been one of the companies that are utilizing the popularity of mobile usage by encouraging websites to use their Google Search Console, the Mobile-Friendly Test, which allows companies to measure up their website to the search engine results and how user-friendly it is.

Flash is a propriety plug-in created by Macromedia to infuse (albeit) fantastically rich media for your websites. The W3C advises you avoid the use of such proprietary technology to construct an entire site. Instead, build your site with CSS and HTML ensuring everyone, including search engine robots, can sample your website content. Then, if required, you can embed media files such as Flash in the HTML of your website.

If you have original, quality content on a site, you also have a chance of generating inbound quality links (IBL). If your content is found on other websites, you will find it hard to get links, and it probably will not rank very well as Google favours diversity in its results. If you have original content of sufficient quality on your site, you can then let authority websites – those with online business authority – know about it, and they might link to you – this is called a quality backlink.
An SEO technique is considered white hat if it conforms to the search engines' guidelines and involves no deception. As the search engine guidelines[18][19][52] are not written as a series of rules or commandments, this is an important distinction to note. White hat SEO is not just about following guidelines but is about ensuring that the content a search engine indexes and subsequently ranks is the same content a user will see. White hat advice is generally summed up as creating content for users, not for search engines, and then making that content easily accessible to the online "spider" algorithms, rather than attempting to trick the algorithm from its intended purpose. White hat SEO is in many ways similar to web development that promotes accessibility,[53] although the two are not identical.
Companies that employ overly aggressive techniques can get their client websites banned from the search results. In 2005, the Wall Street Journal reported on a company, Traffic Power, which allegedly used high-risk techniques and failed to disclose those risks to its clients.[15] Wired magazine reported that the same company sued blogger and SEO Aaron Wall for writing about the ban.[16] Google's Matt Cutts later confirmed that Google did in fact ban Traffic Power and some of its clients.[17]
Google has a LONG list of technical requirements it advises you meet, on top of all the things it tells you NOT to do to optimise your website. Meeting Google’s technical guidelines is no magic bullet to success – but failing to meet them can impact your rankings in the long run – and the odd technical issue can actually severely impact your entire site if rolled out across multiple pages.
The biggest advantage any one provider has over another is experience and resource. The knowledge of what doesn’t work and what will hurt your site is often more valuable than knowing what will give you a short-lived boost. Getting to the top of Google is a relatively simple process. One that is constantly in change. Professional SEO is more a collection of skills, methods and techniques. It is more a way of doing things, than a one-size-fits-all magic trick.
In 2007, Google announced a campaign against paid links that transfer PageRank.[30] On June 15, 2009, Google disclosed that they had taken measures to mitigate the effects of PageRank sculpting by use of the nofollow attribute on links. Matt Cutts, a well-known software engineer at Google, announced that Google Bot would no longer treat any nofollow links, in the same way, to prevent SEO service providers from using nofollow for PageRank sculpting.[31] As a result of this change the usage of nofollow led to evaporation of PageRank. In order to avoid the above, SEO engineers developed alternative techniques that replace nofollowed tags with obfuscated JavaScript and thus permit PageRank sculpting. Additionally several solutions have been suggested that include the usage of iframes, Flash and JavaScript.[32]
For example, let’s say you were running the website of an online pet store. You might be wise to create one keyword grouping for all your dog-related products, then one for all of your parakeet-related projects, etc. The next step would be to segment each individual group into smaller subgroups (parakeet cages, parakeet toys, parakeet snacks) and then even smaller groups for each type of product (low-fat parakeet snacks, luxury parakeet snacks… you get the idea). Now your pet store can create individual pages optimized for each small keyword group.